LU-3259 clio: cl_lock simplification

[fs/lustre-release.git] / lustre / lov / lov_cl_internal.h

diff --git a/lustre/lov/lov_cl_internal.h b/lustre/lov/lov_cl_internal.h
index e9d28f8..0926166 100644 (file)
--- a/lustre/lov/lov_cl_internal.h
+++ b/lustre/lov/lov_cl_internal.h
@@ -280,87 +280,27 @@ struct lov_object {
 };
 
 /**
- * Flags that top-lock can set on each of its sub-locks.
- */
-enum lov_sub_flags {
-        /** Top-lock acquired a hold (cl_lock_hold()) on a sub-lock. */
-        LSF_HELD = 1 << 0
-};
-
-/**
  * State lov_lock keeps for each sub-lock.
  */
 struct lov_lock_sub {
-        /** sub-lock itself */
-        struct lovsub_lock  *sub_lock;
-        /** An array of per-sub-lock flags, taken from enum lov_sub_flags */
-        unsigned             sub_flags;
-        int                  sub_stripe;
-        struct cl_lock_descr sub_descr;
-        struct cl_lock_descr sub_got;
+       /** sub-lock itself */
+       struct cl_lock          sub_lock;
+       /** Set if the sublock has ever been enqueued, meaning it may
+        * hold resources of underlying layers */
+       unsigned int            sub_held:1,
+                               sub_initialized:1;
+       int                     sub_stripe;
 };
 
 /**
  * lov-specific lock state.
  */
 struct lov_lock {
-        struct cl_lock_slice   lls_cl;
-        /** Number of sub-locks in this lock */
-        int                    lls_nr;
-        /**
-         * Number of existing sub-locks.
-         */
-        unsigned               lls_nr_filled;
-        /**
-         * Set when sub-lock was canceled, while top-lock was being
-         * used, or unused.
-         */
-       unsigned int           lls_cancel_race:1,
-                               lls_ever_canceled:1;
-        /**
-         * An array of sub-locks
-         *
-         * There are two issues with managing sub-locks:
-         *
-         *     - sub-locks are concurrently canceled, and
-         *
-         *     - sub-locks are shared with other top-locks.
-         *
-         * To manage cancellation, top-lock acquires a hold on a sublock
-         * (lov_sublock_adopt()) when the latter is inserted into
-         * lov_lock::lls_sub[]. This hold is released (lov_sublock_release())
-         * when top-lock is going into CLS_CACHED state or destroyed. Hold
-         * prevents sub-lock from cancellation.
-         *
-         * Sub-lock sharing means, among other things, that top-lock that is
-         * in the process of creation (i.e., not yet inserted into lock list)
-         * is already accessible to other threads once at least one of its
-         * sub-locks is created, see lov_lock_sub_init().
-         *
-         * Sub-lock can be in one of the following states:
-         *
-         *     - doesn't exist, lov_lock::lls_sub[]::sub_lock == NULL. Such
-         *       sub-lock was either never created (top-lock is in CLS_NEW
-         *       state), or it was created, then canceled, then destroyed
-         *       (lov_lock_unlink() cleared sub-lock pointer in the top-lock).
-         *
-         *     - sub-lock exists and is on
-         *       hold. (lov_lock::lls_sub[]::sub_flags & LSF_HELD). This is a
-         *       normal state of a sub-lock in CLS_HELD and CLS_CACHED states
-         *       of a top-lock.
-         *
-         *     - sub-lock exists, but is not held by the top-lock. This
-         *       happens after top-lock released a hold on sub-locks before
-         *       going into cache (lov_lock_unuse()).
-         *
-         * \todo To support wide-striping, array has to be replaced with a set
-         * of queues to avoid scanning.
-         */
-        struct lov_lock_sub   *lls_sub;
-        /**
-         * Original description with which lock was enqueued.
-         */
-        struct cl_lock_descr   lls_orig;
+       struct cl_lock_slice    lls_cl;
+       /** Number of sub-locks in this lock */
+       int                     lls_nr;
+       /** sublock array */
+       struct lov_lock_sub     lls_sub[0];
 };
 
 struct lov_page {
@@ -446,7 +386,6 @@ struct lov_thread_info {
        struct ost_lvb          lti_lvb;
        struct cl_2queue        lti_cl2q;
        struct cl_page_list     lti_plist;
-       struct cl_lock_closure  lti_closure;
        wait_queue_t            lti_waiter;
        struct cl_attr          lti_attr;
 };